1. Field of the Invention
The present invention relates to a complex electronic component to be used for, for example, mobile communication devices, especially to a complex electronic component in which a surface acoustic wave element is mounted in a concave portion of a multilayer substrate and a filter comprising a passive element is disposed within the multilayer substrate.
2. Description of the Related Art
FIG. 4 shows a common cross section of conventional complex electronic components 50 provided with a multilayer substrate 51 inside of which a LC filter is disposed. A concave portion 52 is provided on the top surface of the multilayer substrate 51 and a surface acoustic wave filter 53 as a bare tip is mounted inside of the concave portion 52, an IC 54 and a capacitor 55 being mounted on the top surface of the flat portion of the multilayer substrate 51 except the concave portion 52. The concave portion 52 is covered with a flat cap 56 made of a metal.
However, a concave portion for mounting the surface acoustic wave element and a flat portion for mounting the IC and capacitor should be provided on the top surface of the multilayer substrate in the conventional complex electronic component as described above. In other words, the size of the multilayer substrate becomes large due to two-dimensional arrangement of a plurality of components on the top surface of the multilayer substrate when the number of the component is increased, causing a problem that the size of the complex electronic component also becomes large.